The Home Office has appointed Patsy Wilkinson to oversee the department's borders and immigration work following Oliver Robbins' move to the government's Brexit unit.
Robbins had been in the post for just under a year before he was asked last month to head up the Cabinet Office unit on leaving the European Union. He has since become the permanent secretary of the newly-created Department for Exiting the European Union, which will lead on Britain's exit from the bloc.
Wilkinson, who was handed an MBE in 2015 for her "services to defence", has held a number of senior posts covering defence and national security issues, including leading the Centre for the Protection of National Infrastructure, a government body accountable to MI5 that offers security advice to businesses and organisations on safeguarding the country's key infrastructure.
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According to the Home Office, Wilkinson also led "the delivery of protective security advice" for the London 2012 Olympics during her time at CPNI. She is set to start work in late August.
Announcing the appointment, Home Office permanent secretary Mark Sedwill said he was "very pleased to welcome Patsy to the Home Office".
He added: "Patsy has the capability, leadership and resilience to make a success of this role, which is one of the biggest and most challenging jobs in government. I look forward to working closely with her to keep our country safe and borders secure."
Wilkinson herself said he was "delighted" to be joining the organisation.
"I am very much looking forward to taking up my new role, working with colleagues in the border and immigration services, across government and our many partner organisations," she said.
Sedwill told CSW earlier this year that he had decided to appoint a dedicated second perm sec in order to bolster oversight of the department's key immigration and border agencies – Border Force, UK Visas and Immigration, Immigration Enforcement and the Passport Office.
“Those four institutions are each led by a director general,” the Home Office chief said. “And so I felt it was right to bring in a second perm sec to bring that team together and provide that overall leadership to those operations, to ensure that they’re properly connected and that they’re delivering across the Home Office agenda, contributing to the work we do to cut crime and to prevent terrorism, as much as to control immigration.”
Overseeing immigration will be a particularly complex task in the wake of the Brexit vote, with questions over the future of freedom of movement and the status of EU nationals currently in the UK still to be answered.
Wilkinson's new ministerial boss, home secretary Amber Rudd, told ITV news this week that she did not believe EU citizens currently in the UK would have their right to remain taken away after Brexit.
But she said it remained "a discussion" before Britain entered formal talks with other EU member states on the terms of its exit.